best way to save my wood floor


What is the best way to protect my wood floor from the speaker spikes. I have been using the sound anchor coasters. They are great, but too high off the ground. I have also used pennies, but they are too soft and spike can still get through.
what is thin and sound good? Thanks in advance.
flying
Check out: http://www.audiopoints.com/apcd2.html they make a coupling disk that works extreamly well. I use them on my hard wood floor.
I put thin strips of felt on one side of a 1/4" wooden board, put that face down on the hardwood floor, and put the speakers on top of the board (with spikes).
A sheet of granite the size of the speaker with felt attached to the bottom. A good place to look for this is kitchen counter vendors or tile supply shops. Usually these people have samples, scrap (like from sink cutouts), or will order what ever you need.